Morphologic techniques are applied to dissociated cell cultures of central nervous system tissue. Combined electrophysiology and immunohistochemistry for choline acetyltransferase (ChAT) have provided a functional correlate for ChAT staining. Septal cultures contain a relatively large proportion of ChAT-positive neurons, hippocampal cultures contain none, and spinal cord cultures plated on feeder layers appear enriched for ChAT-positive neurons. Culture preparations are characterized routinely by immunohistochemistry for neuron specific enolase, glial fibrillary acidic protein, and fibronectin as a means of identifying neurons, astroglia, and fibroblasts, respectively. Radioautography is used to localize benzodiazepine binding sites in cerebral cortical cell cultures, and to follow the distribution, in spinal cord cell cultures, of tetanus toxin with time after initial exposure. Retrograde and anterograde axonal transport of various markers have been used to label specific cell bodies or neurites of dorsal root ganglion neurons grown in multicompartment culture chambers.